Example Female: Sarah

Meet Sarah, a motivated woman who is ready to optimize her nutrition for improved health and fitness.

Step 1: Calculate Basal Metabolic Rate (BMR)

To begin, Sarah needs to calculate her Basal Metabolic Rate (BMR), which determines the calories her body requires at rest. Using the Harris-Benedict equation, let's find Sarah's BMR:

Sarah's weight: 140 pounds Sarah's height: 5 feet 6 inches (66 inches) Sarah's age: 28 years

Sarah's BMR = 655 + (4.35 × 140) + (4.7 × 66) - (4.7 × 28) = 655 + 609 + 310.2 - 131.6 = 1,442.6 calories/day

Step 2: Calculate Total Daily Energy Expenditure (TDEE)

Now, let's determine Sarah's Total Daily Energy Expenditure (TDEE) by multiplying her BMR with her activity level. Sarah leads an active lifestyle, so we'll use an activity factor of 1.725:

Sarah's TDEE = 1,442.6 calories/day × 1.725 = 2,489.335 calories/day

Step 3: Determine Target Calories based on Goal

Sarah's goal is to maintain her current weight. Since maintenance requires consuming calories equal to her TDEE, there is no need for adjustments:

Sarah's Target Calories = 2,489 calories/day

Step 4: Set Macronutrient Breakdown

Sarah prefers a high-protein approach for her diet. She selects the High Protein breakdown:

40% Protein, 30% Carbohydrates, 30% Fat

Step 5: Calculate Macronutrient Caloric Needs

To find the calorie contribution of each macronutrient, we'll multiply the percentage by the target daily calorie intake:

Protein: 0.30 × 2,512 calories/day = 753.6 calories/day

Carbohydrates: 0.40 × 2,512 calories/day = 1,004.8 calories/day

Fat: 0.30 × 2,512 calories/day = 753.6 calories/day

Step 6: Convert Calories to Grams

Lastly, let's convert the calorie contribution of each macronutrient to grams using the calorie-per-gram values:

1g Protein = 4 calories 1g Carbohydrates = 4 calories 1g Fat = 9 calories

Protein: 1,004.8 calories/day ÷ 4 calories/gram = 251.2 grams/day

Carbohydrates: 753.6 calories/day ÷ 4 calories/gram = 188.4 grams/day

Fat: 753.6 calories/day ÷ 9 calories/gram = 83.7 grams/day

Great job, Sarah! You have successfully determined your macronutrient needs. By understanding your BMR, calculating your TDEE, setting your target calorie intake, and customizing your macronutrient breakdown, you're well-equipped to achieve your health and fitness goals. Keep up the great work!